Electrapini, ENGEL, NOMEN TRANSLATUM, 1998

ENGEL, MICHAEL S., 2001, A Monograph Of The Baltic Amber Bees And Evolution Of The Apoidea (Hymenoptera), Bulletin of the American Museum of Natural History 2001 (259), pp. 1-1 : 1-

Key to Genera of Electrapini

1. Metabasitarsus elongate, 1.5–2 times as long as maximum width (fig. 65)........................... Electrapis Cockerell

– Metabasitarsus quadrangular, as long as maximal width (figs. 70, 78, 81)......... 2

2. Lateral margins of clypeus strongly concave, epistomal sulcus forming an obtuse angle opening toward compound eye (fig. 69)................. Protobombus Cockerell

– Lateral margins of clypeus linear, epistomal sulcus straight (figs. 79, 80)..................... Thaumastobombus , n. gen.